CHAPTER III. 
THE COAL SEAMS OF THE LOWER COAL MEASURES 
OF OHIO—Continued. 
Mines oF TRUMBULL, MAHONING, COLUMBIANA, JEFFERSON, PorT- 
AGE, STARK (EXCLUDING THE MAssILLON FIELD), CARROLL, 
TUSCARAWAS, AND GUERNSEY COUNTIES. 
By Epwarp OrTOoN. 
The general features of the several seams have been roughly 
sketched in chapter II, and an equally brief description of the develop- 
ment of these seams in their several districts is next in order. This 
review of the coal fields ot the State is, however, to be regarded as 
supplementary to the reports already published by the Survey, and not 
by any means as a full statement of the geology of the districts. Such 
errors as have been revealed in the sections or details of this earlier 
work, in the course of subsequent exploration or development, will be 
pointed out, and special attention will be given to the fields that have 
been opened since the publication of the previous reports. 
CoaL MIneEsS oF TRUMBULL COUNTY. 
The coal field of Trumbull county is mainly confined to the five 
southeastern townships, viz., Hubbard, Brookfield, Liberty, Vienna, 
and Weathersfield. They constitute the most important, and in every 
way characteristic of the block coal fields of the State. For many 
years they produced more coal and better, not only than any other 
equal area in Ohio, but they placed Trumbull far in the lead of the 
coal-producing counties, but the output is rapidly declining, both 
relatively and absolutely, and a large part of the territory is already 
exhausted. Almost every farm has been tested by borings, but so 
irregular are the deposits of the coal, and so abrupt are their boundaries, 
that it is not safe to say that there are not workable beds under any 
